Straight out of the trench,"Bullshit!" Every backhoe operator in the world with 8 hours experience is worried about the trench walls collapsing and the 'hoe falling into the trench. This is the reason why wood and other materials are used to widen the footpad area. This spreads the weight stress out further. I have seen trenches collapse because the pads weren't widened enough and when the walls collapsed one leg and wheel were buried.
The operator would know just from the 'feel' of the earth being removed whether it was too wet/sloppy to have a man down in the unprotected trench.
The idiot down in the trench should have known but like any other kid, he was relying on the operators experience to protect him.
He had probably seen the operator ask for braces using the excuse, "It'll collapse and we'll lose our tools or screw up the new pipe joint being installed". It's not cool to whine about a man's safety on the job. You go to an ignorant boss and explain the "costs/loss in time" if the walls collapse.
I would go after the owner and the operator. Why? Because they are the ones who know the laws and the hazards.
If any of you don't have an idea what I'm talking about, the next time you see a mobile crane working just look at the different materials used under the footpads to keep the crane sturdy. 12" X 12" X 16' are very common timbers used for 50 ton cranes. It will crush thick asphalt, break thin concrete sidewalks and crush the pipes underground if the footpad stress isn't spread out. (Yes, I'm experienced in that work)
Caution: Anytime you see a crane operating with the boom at a high angle, know that he is working heavy loads and stay twice the length of the boom away from the work site.